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What is a fuel Pressure Regulator?
Okay, so the name might make it sound a little complex, but a fuel pressure regulator is actually a very simple part of your car’s fuel system.
The role of the fuel pressure regulator is remarkably simple, and exactly as the name suggests: It regulates fuel pressure. You don’t want too much or too little gasoline being fed to the fuel injectors, so the regulator maintains the proper amount of fuel pressure, to make for a happy fuel system.
Now, there are two main types of fuel pressure regulators that your car may have. On most older cars, the fuel pressure regulator is located outside of the fuel tank. The fuel pump sends more gasoline than is needed out of the tank, and the regulator intercepts it before it gets to the fuel injectors. The fuel pressure regulator allows the right amount of gas to pass through, and sends the rest of it right back into the gas tank. A little old school, so you can probably guess how newer cars operate.
But in case you can’t guess, newer cars have a simpler, more efficient, and much more reliable fuel pressure regulator, which is built directly into the fuel tank. These types of regulators control the fuel pressure before it leaves the tank, ensuring that the perfect amount of gas is pumped out.
Fuel pressure regulators, especially on newer cars, don’t need to be replaced often at all. They’re rather durable. But they can be subject to wear and tear, at which point they’ll need to be replaced. In older cars, this usually means replacing the fuel pump as well.
Symptoms of a failing Fuel Pressure Regulator
Check engine warning light
Look, I get it. The check engine light is small and unassuming, and your car is driving fine, so what could possibly be wrong?
Well, for starters, your fuel pressure regulator could need replacing. If your fuel pressure regulator is calling in sick, your engine will be getting a weird amount of fuel, and that will likely lead the check engine light coming on.
Poor engine performance
If you're going to ignore the check engine light, at least don’t ignore engine performance.
Especially if your fuel pressure regulator isn’t working. You’ll notice an engine that isn’t quite right. You may have a loss of power, as well as some hesitation and jerkiness. You’ll also likely experience a decrease in fuel efficiency.
Car won’t start
Fun fact: If your car won’t turn on, there’s probably something wrong with it.
Often times a busted fuel pressure regulator will mean that your car isn’t getting enough fuel. That can lead to the car stalling when you’re idling. It’ll be like that one time you tried to learn how to drive a stick shift.
Worse yet, it can lead to the car not turning on at all, which makes it a little difficult to drive.
Dark smoke from the exhaust
If you’ve seen a lot of cars in your life, you should be fairly familiar with what exhaust smoke looks like. If your car has exhaust smoke that looks irregular...well, it's time to put two and two together.
A malfunctioning fuel pressure regulator will upset your engine, and that will often result in very dark plumes of exhaust from your tail pipes.
How urgent is a Fuel Pressure Regulator replacement?